Ferrulate

The mounting cup (ferrule for botde valves) mechanically joins the valve to the container. The mounting cup may be made from a variety of materials, but is typically tin-plated steel coated on the underside. It contains the gasket which provides the seal. Soft gasketing material is appHed wet and bonded in place or, more frequently in larger cans, cut mbber, polyethylene, or polypropylene gaskets are used. 

Hoses must be made for anhydrous ammonia service 2500 kPa (348 psig) working pressure and stamped for this service. In locations where hoses may be abraded, wke braid armored or reinforced hose types should be used. Hose ends should have boss or other acceptable ak kon ferruled couplings. 

Phosphorized deoxidized arsenical copper (alloy 142 (23)) is used for heat exchangers and condenser tubes. Copper-arsenical leaded Muntz metal (alloy 366), Admiralty brass (alloy 443), naval brass (alloy 465), and aluminum brass (alloy 687), all find use in condensers, evaporators, ferrules, and heat exchanger and distillation tubes. The composition of these alloys is Hsted in Table 5. 

The component materials comply with apphcable ASTM specifications, but alter manufacture the outer component may increase in hardness beyond specification limits, and special care is required during the tube-rolling operation. When the harder material is on the outside, precautions must be exercised to expand the tube properly. When the inner material is considerably softer, rolling may not be practical unless ferrules of the soft material are used. 

In order to ehminate galvanic action the outer tube material may be stripped from the tube ends and replaced with ferrules of the inner tube material. When the end of a tube with a ferrule is expanded or welded to a tube sheet, the tube-side fluid can contact only the inner tube material, while the outer material is exposed to the shell-side fluid. 

For inlet or outlet end erosion-corrosion, either extend tube ends 3 or 4 inches into the water box or install sleeves, inserts, or ferrules into the tube ends. These should be a minimum of 5 inches long. The ferrules may be nonmetallic or erosion-resistant metals, such as stainless steel, if galvanically compatible. The end of the ferrule should be feathered to prevent turbulence. 

Turbulence created at the inlet end resulted in erosion-corrosion. Problems of this type can be remedied by using appropriate inserts or ferrules. 

Zwinge,/, clamp, cramp vise ferrule, hoop, zwingen, v.t. force, compel, constrain subdue, conquer, — zwingend, p.a. cogent, compelling. 

Tubes may be inserted into a tubesheet, and packing may be added between them and the tubesheet. A threaded ferrule is inserted to tighten the packing. This type of joint is used only for special expansion problems. 

If conditions are such as to require a duplex tube, it is quite likely that a plain end detail for the tube will not be satisfactory. Grooved or serrated joints are recommended for this type of tube, and the ends should be flared or beaded. Table 10-8 gives recommended flare or bell radii for copper-based alloys. Also see Table 10-8A. In service where galvanic corrosion or other corrosive action may take place on the outside material used in the tube, a ferrule of inside tube... 

Duplex Tube Beaded or Belled This Tube May also be Installed Plain End (No Ferrule)or Flared With or Without Ferrule. 

By reducing the heat-transfer rate at the front tubeplate using insulating ferrules in the tube ends. 

The tube-side inlet to an exchanger, i.e. the tube ends, is a highly turbulent region and nylon ferrules in the tube ends of the inlet pass have been used in cupro-nickel-tubed condensers to prevent erosion. Where the flow is two phase the same rules will apply except that an erosion velocity limit is more difficult to specify. 

The cause of the weaker G dependence must be ascribed to some particular feature of geometry, although exactly what it is has not been found. All of the three bundles involved had their rods supported and correctly positioned by wires wrapped helically around certain of the rods, and it is possible that the wires caused an unfavorable distribution of steam and water. However, it is doubtful that the wire wraps were themselves responsible, since several of the bundles conforming to Eq. (28) were also wire wrapped. (Other devices used for rod supports are suitably spaced grids and ferrules.) The explanation most probably lies in a combination of the effects of the wire wraps with the effects of given rod diameters and rod spacings. For ease of identification, the data that conform with Eq. (28) are hereafter called normal data. 

The bimolecular rate constants were determined (Burke 2001) for the repair of carotenoid radical cations by trolox, ascorbic, ferrulic, and uric acids from the pulse radiolysis studies of carotenoids in aqueous micellar solutions (see Table 14.10). 

As can be seen, all the water-soluble compounds are capable of quenching CAR + efficiently, with rate constants of the order of 106,107, and 108 M 1 s 1 for ferrulic acid, both ascorbic and uric acids, and Trolox, respectively. 

CAR + max(nm) Ascorbic Acid Trolox Ferrulic Acid Uric Acid... 

Their common function is to hold the fibre and to align it with another identical size fibre with high repeatability in tolerances as close as possible (Figure 17). The main component of the connector is the ferrule made from... 

The fiber FPI sensor illustrated in Fig. 7.3 can be fabricated by inserting two endface-cleaved optical fibers into a ferrule. The ferrule usually has a diameter... 

All required materials for a PSI system are easily accessible a flask with two ground glass joints (or one joint and an arm), rubber septum, rubber hose, a short length of PEEK tubing ( 0.5 m), a PEEK chromatography fitting (nut and ferrule) and a source of... 

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